Regulator having check valve manifold for use in subsea control circuit

An apparatus for a subsea control module used in a subsea environment, the apparatus comprising:

• a gate valve having flow connections and having a gate movable between the flow connections;
• an actuator connected to the gate valve and being configured to move the gate in response to hydraulic pressure;
• a directional control valve having:
• an input in communication with a hydraulic fluid supply, a vent in communication with the subsea environment, a pilot in communication with a pilot supply, and an output, the directional control valve configured in closed and opened states in response to the pilot supply at the pilot, the directional control valve in the opened state communicating the hydraulic fluid supply at the input with the output, the directional control valve in the closed state communicating the output with the vent;
• and
• a regulator having a supply and an outlet and having a seal arrangement between the supply and the outlet, the supply in communication with the output of the directional control valve, the outlet in communication with the actuator, the regulator being configured to reduce hydraulic fluid pressure of the hydraulic fluid supply communicated from the supply to the outlet, the seal arrangement being configured to prevent communication of the hydraulic fluid pressure on the outlet to the supply, the regulator having a check valve connecting the supply with the outlet, the check valve being configured to permit at least a portion of the hydraulic fluid pressure at the outlet to bypass the seal arrangement from the outlet to the supply of the regulator to the directional control valve.

A regulator to regulate hydraulic pressure of hydraulic fluid for an actuator of a gate valve of a subsea control module in a subsea environment, the regulator comprising:

• a housing having a supply and an outlet, the housing defining an interior communicating with the supply and the outlet;
• a container movably disposed in the interior in response to the hydraulic pressure in the interior;
• a seal arrangement disposed on the container and being movable with the container relative to the supply and the outlet, the seal arrangement being configured to reduce the hydraulic pressure of the hydraulic fluid communicated from the supply to the outlet, the seal arrangement being configured to prevent communication of the hydraulic pressure on the outlet to the supply;
• and
• a check valve disposed in communication between the supply and the outlet, the check valve being configured to permit at least a portion of the hydraulic pressure at the outlet to bypass the seal arrangement from the outlet to the supply.

A method used for a subsea control module in a subsea environment, the method comprising:

• activating an actuator for a gate valve by:
• opening a directional control valve communicating a hydraulic fluid supply at an input with an output, and
• reducing hydraulic pressure of the hydraulic fluid supply from the output to the actuator using a regulator having a supply in communication with the output and having an outlet in communication with the actuator;
• and
• deactivating the actuator for the gate valve by:
• closing the directional control valve communicating the output with a vent,
• preventing communication of the hydraulic pressure at the outlet to the supply of the regulator using a seal arrangement in the regulator,
• permitting at least a portion of the hydraulic pressure from the actuator to bypass the seal arrangement to the directional control valve through a check valve connecting the outlet to the supply of the regulator, and
• expelling the hydraulic pressure bypassing the regulator from the vent of the directional control valve to the subsea environment.